The present invention relates to a battery control and alarm system for vehicles such as automobiles.
An automobile battery can be excessively, and even totally, drained if accessories drawing current from the battery are left operating after the engine, driving the alternator or generator, has been stopped. To partially reduce the possibility of so draining the battery, warning systems and delay systems have been developed to sound an alarm when the headlights are left on after the motor has stopped and to automatically turn the headlights off after a given delay period. However, these warning and delay systems typically require relatively complex and expensive circuitry to effect their implementation and cannot conveniently be installed as an aftermarket item or transferred from vehicle to vehicle. Further, such warning and delay systems have generally been used in conjunction only with the headlights, and not the other accessories on a vehicle. Consequently, it is possible that one of these other accessories, such as the interior lights, might be left operating after the motor has been stopped, thereby discharging the vehicle battery.
Automobile theft has reached epidemic proportions in some areas of the country and, accordingly, systems have been developed to sound an alarm if one attempts to enter or start the vehicle without first disarming the system using a special device or code. These protective systems are generally classified into two groups--the first group having a switch on access doors to the vehicle to sound an alarm if any of those doors are opened, and the second group requiring a special ignition key to complete an electrical connection necessary to start the vehicle. These protective systems have significant drawbacks. First, such systems typically do not provide a switch manually operable from inside or outside of the vehicle which one may actuate to sound the alarm system when he believes himself to be in danger. Further, the systems utilizing a special key require complex and, consequently, expensive circuitry.